I'm not even sure that I'll be using it too much for emailing.
I just occasionally miss having the features of a full email client that allow me to properly manage and sort emails.

E.g. emails from sites like aliexpress and ebay. Or sites that constantly send me promotions.
Sorting and saving what I want with labels or folders, and clearing out and deleting the dross.

I recently tried searching for a receipt by the company name, but there were so many promotional emails that I had to scroll a long ways.
So I decided to clear out all the recent junk and select a couple months worth of emails.
But, unless I'm totally oblivious to functions, Gmail would have me individually select each email I want by its icon in order to bulk delete? That seems inefficient.

Even if it turns out I'm an idiot and someone provides instructions for gmail (which I'd certainly appreciate), I'd still like to try some email clients that behave more like old fashioned clients in regards to managing contents.

I don't even care about looks. Give me function over form and I'll take the 90s flashbacks.

Thanks for any suggestions.